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United States Patent |
5,750,580
|
Mayer
,   et al.
|
May 12, 1998
|
Polyurethane elastomers prepared from aliphatic polyisocyanates and
polyesterether polyols
Abstract
This invention relates to polyurethane elastomers produced by the reaction
of polyisocyanates with polyesterpolyether polyols (diester-polyether
diols) using the reaction injection molding process (RIM).
Inventors:
|
Mayer; Eduard (Dormagen, DE);
Gronen; Jurgen (Overath, DE)
|
Assignee:
|
Bayer Aktiengesellschaft (Leverkusen, DE)
|
Appl. No.:
|
661280 |
Filed:
|
June 10, 1996 |
Foreign Application Priority Data
| Jun 16, 1995[DE] | 195 21 798.5 |
Current U.S. Class: |
521/51; 521/160; 521/172; 521/173; 528/67; 528/68; 528/76; 528/77; 528/80; 528/83 |
Intern'l Class: |
C08J 009/04; C08G 018/42; C08G 018/48 |
Field of Search: |
521/51,160,172,173
528/68,67,76,77,80,83
|
References Cited
U.S. Patent Documents
3079350 | Feb., 1963 | Bernstein | 521/172.
|
3164568 | Jan., 1965 | Nordt et al. | 521/172.
|
3483169 | Dec., 1969 | Case et al. | 528/76.
|
4065410 | Dec., 1977 | Schafer | 521/51.
|
4150206 | Apr., 1979 | Jourquin et al. | 521/51.
|
4218543 | Aug., 1980 | Weber et al. | 521/51.
|
4504648 | Mar., 1985 | Otani et al. | 528/76.
|
4529744 | Jul., 1985 | Wood | 521/131.
|
4534907 | Aug., 1985 | Peerman et al. | 521/172.
|
4590219 | May., 1986 | Nissen et al. | 521/51.
|
4604410 | Aug., 1986 | Altenberg | 521/172.
|
4605729 | Aug., 1986 | Barnes et al. | 528/301.
|
4929697 | May., 1990 | Nodelman | 528/76.
|
5001166 | Mar., 1991 | Mafoti | 521/159.
|
5145883 | Sep., 1992 | Saito et al. | 521/172.
|
Foreign Patent Documents |
1337448 | Oct., 1995 | CA.
| |
2736685 | Mar., 1979 | DE.
| |
Primary Examiner: Sergent; Rabon
Attorney, Agent or Firm: Gil; Joseph C., Brown; N. Denise
Claims
What is claimed is:
1. A polyurethane elastomer which optionally contains urea groups and
comprises the reaction product of:
a) at least one liquid polyisocyanate component selected from the group
consisting of aliphatic polyisocyanates, alicyclic polyisocyanates and
mixtures thereof,
b) optionally, one or more isocyanate-reactive compounds having an average
molecular weight of about 1000 to 6000 and an average functionality of at
least two,
c) from about 10 to about 42% by weight, based on 100% by weight of the
reaction mixture without fillers, of at least one isocyanate-reactive
compound comprising a polyesterether polyol having a molecular weight of
less than 500 and a functionality of at least two, wherein said
polyesterether polyol contains from 3 to 7 mol of ester groups/kg of
polyesterether polyol, and an ethylene oxide content of from 40 to 60% by
weight, and said polyesterether polyol consists of the reaction product of
aromatic carboxylic acid anhydrides with (oligo)ethylene glycols, and
subsequent ethoxylation, and
d) 1 to 30% by weight, based on the total weight of all the components, of
fillers,
wherein components a) through d) are reacted via the reaction injection
molding process.
2. The polyurethane elastomer of claim 1, wherein the reaction product
additionally comprises:
e) additives.
3. A process for the production of polyurethane moldings having a closed
surface, a density of greater than 0.9 g/cm.sup.3, optionally contains
urea groups and are optionally cellular, by the reaction injection molding
process of a reaction mixture comprising:
a) at least one liquid polyisocyanate component selected from the group
consisting of aliphatic polyisocyanates, alicyclic polyisocyanates and
mixtures thereof,
b) optionally, one or more isocyanate-reactive compounds having an average
molecular weight of about 1000 to 6000 and an average functionality of at
least two,
c) from about 10 to about 42% by weight, based on 100% by weight of the
reaction mixture without fillers, of at least one isocyanate-reactive
compound comprising a polyesterether polyol having a molecular weight of
less than 500 and a functionality of at least two, wherein said
polyesterether polyol contains from 3 to 7 mol of ester groups/kg of
polyesterether polyol, and an ethylene oxide content of from 40 to 60% by
weight, and said polyesterether polyol consists of the reaction product of
aromatic carboxylic acid anhydrides with (oligo)ethylene glycols, and
subsequent ethoxylation, and
d) 1 to 30% by weight, based on the total weight of all the components, of
fillers.
4. The process of claim 3, wherein said reaction mixture additionally
comprises:
e) additives.
Description
BACKGROUND OF THE INVENTION
This invention relates to polyurethane elastomers comprising the reaction
product of polyisocyanates with polyesterpolyether polyols
(diesterpolyether diols), and a reaction injection molding process (RIM)
for their production.
It is known to produce reinforced, in particular rigid polyurethane
elastomers, optionally containing urea with a density of above 0.9
g/cm.sup.3 using the reaction injection molding process. These are
obtained by crosslinking aromatic polyisocyanates with polyether or
polyester polyols (as described in, for example, DE-A 2,513,817). In
general, an aromatic diamine component, for example DETDA (industrial
mixture of 1-methyl-3,5-diethyl-2,4- and -2,6-diaminobenzene), is added
(as described in, for example, DE-A 3,827,595). Moldings produced in this
manner exhibit excellent mechanical properties, such as modulus of
elasticity, flexural modulus, elongation at break, hardness. They are
suitable for many applications such as, for example, in the automotive
sector.
Disadvantages of using moldings based on aromatic polyisocyanates and/or
aromatic amine components are that they yellow when weathered or exposed
to sunlight and the surface additionally roughens. This makes it necessary
for these moldings to be subsequently lacquer coated for demanding
applications such as, for example, in exterior automotive applications.
It is known, for example from DE-A 2,736,685, that the use of glycols as
crosslinking agents in the reaction with aromatic isocyanates under
current production conditions gives rise to only just tolerable setting
times of at least two minutes.
The prevention of yellowing in PUR systems produced using the reaction
injection molding process is particularly important with regard to
directly colored moldings. PUR systems which give rise to directly colored
moldings allow labor intensive and costly lacquer coating operations to be
dispensed with. In this manner, it is possible to reduce the production
costs of moldings exposed to weathering.
The obvious idea of transferring this experience to elastomers produced
using the RIM process has hitherto failed to come to fruition on the one
hand due to unfavorable demolding times and, on the other hand, due to the
difficulty of incorporating large quantities of fillers, in particular
fibrous or flat fillers, into such formulations (see DE-A 2,736,685 and
DE-A 2,513,817). If, for example, glass fibers are incorporated into a
polyol mixture according to this invention, for example in accordance with
the teaching of DE-A 2,513,897 the polyol mixture separates. This may
cause considerable problems for any industrial use.
The possibility of reliable production and of rapid demolding cycles while
simultaneously achieving elevated mechanical properties, in particular
hardness and flexural modulus, are essential features. It is only in this
case that these materials are suitable as moldings, for example, in
exterior automotive applications. With suitable catalysis, high demolding
times may in particular be improved by using internal release agents.
External release agents cause delays as they must be applied in an
additional operation step.
As DE-A 2,736,685 discloses with regard to formulations based on aliphatic
isocyanates, demolding times of approximately five minutes are generally
required. DE-A 2,710,901 reports tack-free times (not identical to
demolding times) of approximately 1 minute, which are made possible by
specific combinations of catalysts. Demolding times of approximately 30
seconds are achieved (DE-3,827,595) in the industrial production of
moldings for the automotive sector based on aromatic polyisocyanates in
combination with aromatic crosslinking components (such as, for example,
DETDA). It is also possible to incorporate large quantities of fillers
into the elastomer in this process.
It is already known from DE-A 2,622,951 (believed to be the equivalent of
U.S. Pat. No. 4,218,543) and DE-A 3,827,595, to produce polyurea
elastomers containing urethane groups and fillers by the reaction
injection molding process using polyisocyanates or polyisocyanate mixtures
of the diphenylmethane series, relatively high molecular weight polyether
polyols and alkyl-substituted aromatic amines, wherein both the one-shot
process and the semi-prepolymer method may be used.
DE-A 2,513,817 describes the use of polyesters in the crosslinking agent
mixture. However, the addition of polyesters gives rise to unfavorable
glass holding capacity and phase stability (two phases are formed) of the
polyol mixture (loc. cit. example 20). When polyether polyols are used
alone, a substantially softer polymer matrix is moreover obtained. This
may have an unfavorable effect on the mechanical properties of moldings
produced therefrom.
The object of the present invention is to provide an economically
advantageous process which may be performed on an industrial scale which
allows the use of aliphatic or alicyclic polyisocyanates for the
production of colorable polyurethanes with good surfaces or integral skin
surfaces. These colorable polyurethanes are desired to be resistant to
discoloration under the combined action of light and oxygen, and, by
virtue of their physical properties are suitable, for example, for
exterior automotive applications without additional lacquer coating.
It has now surprisingly been found that the use of specific polyesterethers
in the liquid polyol mixture described as the crosslinking agent mixture
during the production of colorable, light-fast polyurethanes based on
aliphatic or alicyclic polyisocyanates results in a series of remarkable
advantages. This is particularly true when fillers are used.
SUMMARY OF THE INVENTION
The present invention provides polyurethane elastomers optionally contain
urea groups and comprises the reaction product of;
a) at least one liquid polyisocyanate component selected from the group
consisting of aliphatic polyisocyanates, alicyclic polyisocyanates and
mixtures thereof,
b) optionally one or more isocyanate-reactive compounds having an average
molecular weight of about 1000 to about 6000 and an average functionality
of at least 2,
c) at least one isocyanate-reactive compound having a molecular weight of
less than 1000, preferably of less than about 500, wherein at least one of
said compounds has a functionality of at least 2,
d) from about 1 to about 30% by weight of fillers, based on the total
weight of all the components of the elastomer,
wherein an isocyanate index of 90 to 120 is maintained and at least one of
the isocyanate-reactive compounds of component c) comprises a polyhydroxyl
compound based on a polyesterether polyol.
The polyurethane elastomers which optionally contain urea groups wherein
the reaction product may additionally comprise:
e) auxiliary substances and additives which are known per se in
polyurethane chemistry.
The polyurethane elastomers according to the invention are produced using
the reaction injection molding process (RIM process).
Thus, the present invention also provides a reaction injection molding
process for the production of optionally cellular, elastic moldings having
a closed surface layer and a density of greater than 0.9 g/cm.sup.3. These
polyurethane elastic moldings which optionally contain urea groups are
prepared from a reaction mixture comprising:
a) at least one liquid polyisocyanate component selected from the group
consisting of aliphatic polyisocyanates, alicyclic polyisocyanates and
mixtures thereof,
b) optionally one or more isocyanate-reactive compounds having an average
molecular weight of about 1000 to about 6000 and an average functionality
of at least 2,
c) at least one isocyanate-reactive compound having a molecular weight of
less than 1000, preferably of less than about 500, and a functionality of
at least 2, and
d) from about 1 to 30% by weight of fillers, based on the total weight of
all the components of the elastomer.
wherein at least one of the isocyanate-reactive compounds in component c)
comprises a polyhydroxyl compound based on a polyesterether polyol.
The reaction mixture which is used in the RIM process to prepare the
optionally cellular polyurethane moldings may additionally comprise:
e) auxiliary substances and additives which are known per se in
polyurethane chemistry.
When fillers are mixed with the polyol component c) which comprises a
polyhydroxyl compound based on a polyesterether polyol in accordance with
the present invention, the mixture is resistant to sedimentation, even for
two or more days. It may straightforwardly be processed using the reaction
injection molding process, i.e. no line blockages occur due to
sedimentation, even when the plant is shut down. The mixture of fillers
with the presently required polyesterether polyol remains as a single
phase mixture.
If, for example, a polyether polyol or a mixture of polyether polyols (as
described in, for example, DE-A 2,736,085) having the same OH value and
functionality as the polyesterether polyol of the crosslinking agent
mixture according to the present invention (example 19) is used, the
incorporation of fillers into this crosslinking agent mixture rapidly
brings about the separation of the filler from the liquid polyol component
(working example 20, analogue DE-A 2,736,685). Separation is also observed
if, in example 19, the component (polyesterether polyol) according to the
invention is removed and replaced by the same weight of the long-chain
polyether (see example 21).
The polyurethane elastomers produced according to the invention may be
colored, and may be processed to yield light-stable and oxygen-resistant
moldings which do not yellow.
The polyesterether polyols used according to the invention
(diesterpolyether diols) have 3 to 7, preferably 5 to 6 mol of ester
groups/kg of polyesterether polyol. These may be produced according to
known methods such as, for example, by the reaction of aromatic carboxylic
acid anhydrides with (oligo)ethylene glycols and subsequent ethoxylation.
They are preferably made from phthalic anhydride, diethylene glycol and
ethylene oxide. These polyesterether polyols have an aromatics content of
40 to 60 wt. %, and an ethylene oxide content --(CH.sub.2 CH.sub.2 O)-- of
40 to 60 wt. %.
The polyesterether polyol used as component c) of the present invention, is
present in amounts of about 10 to 42 wt. %, preferably of about 19 to 42
wt. % (at an isocyanate index of 100), based on 100 wt. % of the reaction
mixture (polymer matrix), without fillers.
The urethane group content relative to the polymer matrix at an index of
100 without fillers is greater than 1.4 mol/kg of elastomer, and
preferably 1.8 to 3 mol/kg of elastomer.
The node density in the elastomer is greater than 0.5, preferably 0.8 to
1.9 mol of nodes/kg of elastomer.
The polyurethane elastomers produced according to the present invention may
be used in automotive construction such as, for example, for the
production of automotive components such as bumpers, door sills and wing
liners, protective bars, etc.
Isocyanate components a) which may be used in accordance with the present
invention are those aliphatic, cycloaliphatic, araliphatic isocyanates as
are described, for example, in Justus Liebigs Annalen der Chemie, 562,
pages 75-136. Aliphatic and cycloaliphatic diisocyanates, such as for
example 1,6-hexamethylene diisocyanate (HDI), 1,4-diisocyanatocyclohexane,
1-isocyanato-2,2,5-trimethyl-5-isocyanato-methylcyclohexane (IPDI),
4,4-diisocyanato-dicyclohexylmethane or xylylene diisocyanate are
preferred and the biuretized and/or allophanatized and/or trimerized
variants of these isocyanates are particularly preferred, in particular
those of HDI or IPDI.
The isocyanate-reactive compounds b) used in accordance with the present
invention are polyether polyols or the mixtures thereof, which are
produced in a manner known per se by alkoxylating suitable starter
molecules or mixtures, wherein propylene oxide is in particular used for
alkoxylation, optionally together with ethylene oxide. The compounds have
an average molecular weight of about 1000 to about 6000 and an average
functionality of at least 2. Suitable starter molecules include, for
example, water, ethylene glycol, propylene glycol, trimethylenepropane,
glycerol, pentaerythritol, sorbitol or cane sugar. Preferred polyether
polyols are those having a primary OH group content of above 50%,
particularly preferably of greater than 70%. Such polyether polyols are
obtained by terminal grafting of ethylene oxide. Polyether polyols
complying with the definition and containing dispersed fillers are also
suitable, as are, for example, polyols obtained by polymerizing
acrylonitrile and/or styrene in the polyethers as the reaction medium (as
described in, for example, DE-A 3,827,595 and the literature cited
therein).
Other isocyanate-reactive compounds c), in addition to the polyether ester
compound c), suitable for use in accordance with the present invention,
have an average molecular weight of less than 1000, preferably of less
than about 500, and include, for example, compounds such as ethylene
glycol, 1,4-butanediol, hexanediol, diethylene glycol, neopentyl glycol or
mixtures thereof. 2-Methyl-1,3-propanediol mixtures may also contain
monofunctional alcohols.
Component d) the fillers are selected from the various mineral or organic
substances, preferably fibers (such as, for example, glass fibers).
Additives and auxiliary substances e) to used in the reaction mixture
according to the present invention include, for example, dyes, pigments,
blowing agents and/or internal release agents such as zinc stearate or
polyetherpolysiloxanes. Such per se known auxiliary substances and
additives are described, for example, in EP-A 81,701.
EXAMPLES
The formulations described in the following examples were processed by
reaction injection molding.
The compounds containing NCO groups (=component A) and component B were
introduced into a high pressure metering unit and, after vigorous mixing
in a positively controlled mixing head, injected as quickly as possible
into a hot metal mold (T=.ltoreq.100.degree. C.), wherein the mold
interior had been coated with a conventional commercial ready-to-use
soap-based external mold release agent RTCW 2006 from Chem Trend.
The steel sheet mold allows the production of test sheets of dimensions
300.times.200.times.3 mm. The mold is filled from the longitudinal side
through a restrictor bar gate.
The elastomers were characterized by their Shore D/A hardness (DIN 53 505),
bulk density (DIN 53 420), stress, tear strength, elongation at break (DIN
53 504) and tear propagation strength (DIN 53 515).
Examples according to the invention are summarized in Tables 1a to 1c;
examples not according to the invention are shown in Table 2. Examples 19
to 24 describe filler holding capacity. The values stated in brackets ›!
are weight percentages in the elastomer (at an index of 100). H:U=mol of
urea: mol of urethane/kg of elastomer (at an index of 100);
##EQU1##
wherein: n: equals the number of all components,
gi: equals parts by weight of component i,
fi: equals functionality of component i,
MWi: equals molecular weight of component i in ›g!; and
if fi: equals 0, then there are 0 mol of nodes/kg.
Aliphatic isocyanate with f=2 and MW=174 reacts with trifunctional polyol
of MW=300
Sample Calculation
______________________________________
1. Isocyanate node
= (2-2)*1000/174 ›mol of
density = 0 nodes/kg!
2. Polyol node = (3-2)*1000/300 ›mol of
density = 3.33 nodes/kg!
3. Aliphatic iso-
= polyol for index = 1
cyanate:polyol
= 87:100
mixing ratio
4. Elastomer node
= (0*87 + 100*3.33)/(87 + 100)
›mol of
density 1.782 nodes/kg!
______________________________________
Description of components used in the examples:
Polyol 1: a polyetherester polyol having an OH value of 310, produced by
reaction of 1 mol of phthalic anhydride with 2 mol of diethylene glycol
and subsequent ethoxylation of the polyester.
Polyol 2: a polyether polyol having an OH value of 28, produced by
propoxylation of propylene glycol and subsequent ethoxylation
(PO:EO=79:21)
Polyol 3: a polyether polyol having an OH value of 630, produced by
propoxylation of ethylenediamine.
Polyol 4: a polyether polyol having an OH value of 28, produced by
propoxylation of trimethylolpropane and subsequent ethoxylation
(PO:EO=86.5:13.5).
Polyol 5: a polyether polyol having an OH value of 550, produced by
ethoxylation of trimethylolpropane
Polyol 6: a polyether polyol having an OH value of 330, produced by
propoxylation of 2-butene-1,4-diol.
Polyol 7: a polyether polyol having an OH value of 190, produced by
propoxylation of propylene glycol and subsequent ethoxylation
(PO:EO=0.6:99.4).
Polyol 8: a polyether polyol having an OH value of 270, produced by
propoxylation of propylene glycol.
Polyol 9: a hexanediol-based polyricinoleic acid ester having an OH value
of 35.
Polyol 10: a polyester prepared from phthalic anhydride and diethylene
glycol having an OH value of 318.
Polyol 11: a polyether polyol having an OH value of 28, produced by
propoxylation of trimethylolpropane and subsequent ethoxylation (PO:EO
weight ratio=78:22).
Polyol 12: Jeffamine D 400.RTM., a polyetherdiamine (based on PO),
commercially available from Texaco, having a molecular weight of 400.
Tinuvin B75.RTM.: a UV stabilizer, commercially available from Ciba Geigy,
NH value=53.
Red paste: a polyether polyol having an OH value of 28, (PO:EO=87:13)
produced by propoxylation of trimethylolpropane and subsequent
ethoxylation, containing approximately 15% of powdered colorant.
Fomrez UL 28.RTM.: dimethyltin dilaurate.
DBTL.RTM.: dibutyltin dilaurate.
Dabco 33 LV.RTM.: 33% solution of triethylenediamine in dipropylene glycol.
B8901.RTM.: a conventional commercial polyetherpolysiloxane from
Goldschmidt, Essen.
A1100.RTM.: aminosilane: 1-amino-3-triethoxysilanepropane.
Tegomer HS 2311.RTM.: .alpha.,.omega.-hydroxyfunctional
polydimethylsiloxanes with a functionality of 2 and an OH value of 45 from
Goldschmidt.
Isocyanate A: hexamethylene diisocyanate trimer, NCO content 21.6%,
functionality approximately 3.5, commercially available from Bayer AG.
MF 7980.RTM.: glass fiber, commercially available from Bayer AG.
TABLE 1a
______________________________________
Examples according to the invention
Example
1 5 8
______________________________________
Polyol 1 87.97 ›36.56!
46.85 ›29.90!
41.43 ›26.46!
Polyol 2 *** 42.16 ›26.91!
49.97 ›31.92!
Ethylene glycol
7.04 ›2.92!
*** ***
Tinuvin B 75 .RTM.
2.46 ›1.02!
1.64 ›1.05!
1.61 ›1.03!
Fomrez .RTM. UL 28
1.94 ›0.82!
1.26 ›0.81!
1.25 ›0.80!
Dabco 33 LV .RTM.
0.48 ›0.20!
0.32 ›0.20!
0.31 ›0.20!
DBTDL .RTM. 0.11 ›0.05!
0.08 ›0.05!
0.08 ›0.05!
Red paste *** 4.68 ›2.99!
***
Polyol 3 *** *** 5.52 ›1.61!
H S 2311 .RTM.
*** 2.15 ›1.38!
2.08 ›1.33!
B 8901 .RTM.
*** 0.84 ›0.54!
0.74 ›0.47!
A 1100 .RTM.
0.005 ›0.002!
0.005 ›0.002!
0.005 ›0.002!
MF 7980 .RTM.
15% 15% 15%
(% in elastomer)
Ratio at index = 100
100.00:140.63
100.00:56.67
100.00:56.58
(pol:iso)
Index 110 110 110
Isocyanate A A A
mol/kg H:U 0.01:2.98 0.01:1.84 0.01:1.84
mol of nodes/kg of
1.301 0.811 0.895
elastomer
Mechanical properties
Shore D 84 54 45
Bulk density
-- 1.263 1.246
(g/cm.sup.3)
Water absorption,
-- 2.17 2.34
1 day (%)
Water absorption,
-- 4.5 4.71
7 days (%)
10% stress (MPa)
0 10 6
100% stress (MPa)
0 0 0
Tear strength
70 13 10
(MPa)
Elongation at break
2 66 80
(%)
SAG test 100 mm
42 54 51
(mm)
SAG test 150 mm
-- -- --
(mm)
Tear propagation
-- 45 23
strength (kN/m)
______________________________________
TABLE 1b
______________________________________
Examples according to the invention (glass content)
Example
9 10
______________________________________
Polyol 1 53.18 ›31.79!
51.08 ›30.53!
Polyol 2 *** 39.33 ›23.50!
Polyol 4 38.67 ›23.11!
***
Tinuvin B 75 .RTM.
1.72 ›1.03! 1.72 ›1.03!
Fomrez UL 28 .RTM.
1.34 ›0.80! 1.34 ›0.80!
Dabco 33 LV .RTM.
0.34 ›0.20! 0.34 ›0.20!
DBTL .RTM. 0.08 ›0.05! 0.08 ›0.05!
Polyol 3 1.66 ›0.99! 3.10 ›1.85!
H S 2311 .RTM. 2.23 ›1.33! 2.23 ›1.33!
B 8901 .RTM. 0.79 ›0.47! 0.79 ›0.47!
A 1100 .RTM. 0.005 ›0.003!
0.005 ›0.002!
MF 7980 .RTM. 15% 15%
(% in elastomer)
Ratio at index = 100
100.00:67.31 100.00:67.33
(pol:iso)
Index 110 110
Isocyanate A A
mol/kg H:U 0.01:2.05 0.01:2.05
mol of nodes/kg of elastomer
1.000 1.000
Mechanical properties
Shore D 68 63
Sheet thickness (mm)
2.80 2.81
Bulk density (g/cm.sup.3)
1.279 1.319
Water absorption, 1 day (%)
0.66 0.92
Water absorption, 7 days (%)
1.55
10% stress (MPa) 24 27
100% stress (MPa)
0 0
Tear strength (MPa)
26 27
Elongation at break (%)
14 13
SAG test 100 mm (mm)
61 67
SAG test 150 mm (mm)
-- --
Tear propagation strength (kN/m)
53 64
Shrinkage (longitudinal) (%)
0.609 0.561
Shrinkage (transverse) (%)
1.050 1.334
______________________________________
TABLE 1c
______________________________________
Examples according to the invention
Example
11 12 13 14
______________________________________
Polyol 1 51.08 49.54 50.63 54.31
›30.53! ›29.97! ›30.43! ›31.48!
Polyol 2 39.33 38.14 38.99 31.53
›23.50! ›23.07! ›23.43! ›18.28!
Polyol 5 *** *** *** 2.37
›1.95!
Jeffamine D
*** *** *** 3.19
400 .RTM. ›1.85!
Polyol 12
Tinuvin B
1.72 ›1.03!
1.67 ›1.01!
1.71 ›1.03!
1.77
75 .RTM. ›1.03!
Fomrez UL
1.34 ›0.80!
1.30 ›0.79!
1.33 ›0.80!
1.38
28 .RTM. ›0.80!
Dabco 33 0.34 ›0.20!
0.33 ›0.20!
0.34 ›0.20!
0.35
LV .RTM. ›0.20!
DBTDL .RTM.
0.08 ›0.05!
0.08 ›0.05!
0.08 ›0.05!
0.08
›0.05!
Polyol 3 3.10 ›1.85!
3.01 ›1.82!
3.07 ›1.85!
***
Zinc stearate
*** 3.01 ›1.82!
3.07 ›1.85!
3.10
›1.85!
H S 2311 .RTM.
2.23 ›1.33!
2.16 ›1.31!
*** ***
B 8901 .RTM.
0.79 ›0.47!
0.77 ›0.46!
0.78 ›0.47!
0.81
›0.47!
A 1100 .RTM.
0.005 0.005 0.005 0.005
›0.003! ›0.003! ›0.003! ›0.003!
MF 7980 .RTM.
15% 15% 15% 15%
(% in
elastomer)
Ratio at 100.00:67 100.00:65 100.00:66
100.00:7
index = 100
.33 .31 2.52
(pol:iso)
Index 110 110 110 110
Isocyanate
A A A A
mol/kg H:U
0.01:2.05 0.01:2.05 0.01:2.01
0.1:2.05
mol of nodes/
1.000 0.982 0.992
1.000
kg of elastomer
Mechanical
properties
Shore D 60 59 63 66
Sheet thickness
2.81 2.80 2.85 2.81
(mm)
Bulk density
1.35 1.21 1.26 0.84
(g/cm.sup.3)
Water 1.35 1.21 1.26 0.84
absorption,
1 day (%)
10% stress
15 18 19 19
(MPa)
100% stress
0 0 0 0
(MPa)
Tear strength
15 19 20 20
(MPa)
Elongation at
63 58 41 84
break (%)
SAG test 100
50 53 36 20
mm (mm)
SAG test 150
-- -- -- 78
mm (mm)
Tear 60 66 69 77
propagation
strength (%)
Shrinkage
0.579 0.825 0.886
0.713
(longitudinal)
(%)
Shrinkage
1.254 1.409 1.313
1.465
(transversal)
(%)
Release satisfactory
good to good good
behavior - very good
sprue
Release good very good very good
very good
behavior -
sheet
______________________________________
TABLE 2a
______________________________________
Examples not according to the invention
Example
16 17 18
______________________________________
Polyol 2 26.10 ›15.60!
42.66 ›25.49!
***
Polyol 6 *** 47.70 ›28.51!
46.70 ›27.91!
Polyol 7 14.28 ›8.53!
*** ***
Polyol 8 49.98 ›29.87!
*** ***
Polyol 9 *** *** 43.66 ›26.09!
Polyol 3 3.09 ›1.85!
3.10 ›1.85!
3.10 ›1.85!
Tinuvin B 75 .RTM.
1.77 ›1.06!
1.77 ›1.06!
1.77 ›1.06!
Fomrez UL 28 .RTM.
1.34 ›0.80!
1.34 ›0.80!
1.34 ›0.80!
Dabco 33 LV .RTM.
0.34 ›0.20!
0.34 ›0.20!
0.34 ›0.20!
DBTDL .RTM. 0.08 ›0.05!
0.08 ›0.05!
0.08 ›0.05!
H S 2311 .RTM.
2.23 ›1.33!
2.23 ›1.33!
2.23 ›1.33!
B 8901 .RTM.
0.79 ›0.47!
0.79 ›0.47!
0.79 ›0.47!
A 1100 .RTM.
0.005 ›0.003!
0.005 ›0.003!
0.005 ›0.003!
MF 7980 15% 15% 15%
(% in elastomer)
Ratio at index =
100.00:67.34
100.00:67.34
100.00:67.34
100 (pol:iso)
Index 110 110 110
Isocyanate A A A
mol/kg H:U 0.01:2.05 0.01:2.05 0.01:2.05
mol of nodes/kg
1.000 1.000 1.000
of elastomer
Mechanical properties
Shore D 23 23 20
______________________________________
Mechanical properties could not be measured as the moldings could easily be
torn by hand.
Examples of filler holding capacity of polyol formulations:
Sedimentation properties:
Equipment:
Laboratory stirrer (from Jahnke & Kunkel)
Paddle agitator, .o slashed. 100 mm
Tinplate can, 1000 ml
Measuring cylinder (500:5) DIN In 20.degree. C..+-.2.5 ml
Method:
The polyol mixtures listed in table 3 were initially introduced into a 1000
ml tinplate can. The appropriate quantity of glass fiber (MF 7980) was
added at room temperature and stirred in within 5 minutes with a
laboratory paddle stirrer (.o slashed. 100 mm) at a maximum stirring speed
of 1000 rpm.
500 ml (500 scale divisions) of the polyol/glass fiber mixture were then
transferred into a measuring cylinder.
Evaluation:
At the beginning of measurement, the glass fibers were observed to be
uniformly distributed over the entire measuring scale (500 scale
divisions).
The sedimentation value stated in the table (glass/polyol "phase
separation") describes the height of the settled glass fibers (scale
divisions) in the polyol component after 70 hours at room temperature.
TABLE 3
__________________________________________________________________________
Sedimentation of glass fibers in polyol mixtures according to the
invention and not according to the invention
Example
19 20 21 22 23 24
__________________________________________________________________________
Phase separation.sup.a)
none yes none none yes yes
Polyol 1 51.08 *** *** *** *** ***
Polyol 10 *** 51.08 *** *** *** ***
Polyol 7 *** *** *** 14.28 *** ***
Polyol 8 *** *** *** 49.98 *** ***
Polyol 2 39.33 39.33 90.41 26.1 *** ***
Polyol 11 *** *** *** *** 75.20 78.20
Ethylene glycol
*** *** *** *** 21.20 21.20
DETDA .RTM.
*** *** *** *** 6.00 ***
Tinuvin B 75
1.72 1.72 1.72 1.77 *** ***
Fomrez UL 28 .RTM.
1.34 1.34 1.34 1.34 *** ***
Dabco 33 LV .RTM.
0.34 0.34 0.34 0.34 0.50 0.50
DBTDL .RTM.
0.08 0.08 0.08 0.08 0.10 0.10
Polyol 3 3.10 3.10 3.10 3.10 *** ***
H S 2311 .RTM.
2.23 2.23 2.23 2.23 *** ***
B 8901 .RTM.
0.79 0.79 0.79 0.79 *** ***
A 1100 .RTM.
0.005 0.005 0.005 0.005 *** ***
OH value/functionality
193.3/2.11
193.3/2.11
49.3/2.49
193.4/2.11
431.0/2.03
407.0/2.04
Polyol (%)
76.5
69.7
76.5
69.7
76.5
69.7
76.5
69.7
76.5
69.7
76.5
69.7
Glass fiber MF 7980
23.5
30.3
23.5
30.3
23.5
30.3
23.5
30.3
23.5
30.3
23.5
30.3
(%)
Sedimentation
500 500 190 260 260 350 170 240 310 430 410 490
(scale divisions).sup.b)
__________________________________________________________________________
.sup.a) compatability of the polyol formulation
500 .DELTA. not settled
.sup.b separation of polyols and glass fibers
Although the invention has been described in detail in the foregoing for
the purpose of illustration, it is to be understood that such detail is
solely for that purpose and that variations can be made therein by those
skilled in the art without departing from the spirit and scope of the
invention except as it may be limited by the claims.
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